openwrt-xburst/package/busybox/patches/243-udhcpc_changed_ifindex.patch

--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -1144,6 +1144,12 @@ int udhcpc_main(int argc UNUSED_PARAM, c
 		/* silence "uninitialized!" warning */
 		unsigned timestamp_before_wait = timestamp_before_wait;
 
+		/* When running on a bridge, the ifindex may have changed (e.g. if
+		 * member interfaces were added/removed or if the status of the
+		 * bridge changed).
+		 * Workaround: refresh it here before processing the next packet */
+		udhcp_read_interface(client_config.interface, &client_config.ifindex, NULL, client_config.client_mac);
+
 		//bb_error_msg("sockfd:%d, listen_mode:%d", sockfd, listen_mode);
 
 		/* Was opening raw or udp socket here